Browse Topic: Nanotechnology

Items (1,652)
ABSTRACT The purpose of this project was to study the underlying fundamental phenomena associated with the formation of dendrites in Lithium-metal batteries through the use of in-situ optical microscopy, and other techniques, and develop material solutions to suppress dendritic growth, such as carbon (graphene) nanoribbons (CNRs). Throughout the course of this effort, sixteen different slurry compositions were prepared and made into a total of 96 electrodes (six of each composition). These electrodes were built into in-situ optical cells and coin half-cells and then tested using in-situ optical microscopy and cycle testing. The results found that the inclusion of CNRs generally reduced the severity of dendrite formation. Citation: D. Skalny, J. Mainero, E. Joseph, M. Anger, B. Fahlman, “Fundamental Study on the Suppression of Dendrite Growth in Lithium-Metal Batteries via Carbon Nanoribbons Through In-Situ Optical Microscopy”, In Proceedings of the Ground Vehicle Systems Engineering
Skalny, DavidMainero, JamesJoseph, EliseAnger, MichaelFahlman, Bradley
ABSTRACT Additions of both carbon fiber (CF) and carbon nano-tubes (CNTs) as reinforcements to polyurea (PUr) based adhesives are computationally investigated. Both CF and CNTs show an increase in stiffness. The effect of CF reinforcements on the PUr is more pronounced than the CNT’s but this due to CNT loading being dramatically lower. On percent basis the CNT effect on strength was greater than the CF. Increasing hard segment content of PUr also had a positive effect on the joint strength, but a negative effect on the shear joint displacement. Finally the addition of CF reinforcements moved the performance of a PUr formulation from a Group IV adhesive into the Group III category. This paper illustrates the potential for commonly available reinforcements to be used to tailor the strength elongation characteristic of a PUr adhesive system. Citation: Demetrios A. Tzelepis, Robert Hart, “Optimization of Nano-Enhanced Elastomeric Adhesives Through Combined Experimental and Computational
Tzelepis, Demetrios A.Hart, Robert
ABSTRACT Titanium and its alloys offer superior strength at a fraction of the weight of steel or nickel-based alloys. Some α-β titanium alloys such as Ti-6Al-4V have been widely used in laser powder bed fusion additive manufacturing applications due to the historical cast-wrought data sets and the availability of this alloy in powder form, however this alloy presents challenges during the laser-based printing process of components due to the high residual stress in the material. Alternative β-rich Ti alloys such ATI Titan 23™ can offer superior printability, lower residual stress, and higher mechanical properties than Ti-6Al-4V in additive manufacturing applications. This study covers the assessment of ATI Titan 23™ as an alternative printable Ti alloy and the resulting microstructure, mechanical properties, and residual stress of the printed material. Citation: Garcia-Avila, Foltz, “Low Distortion Titanium Alloy in Laser Powder Bed Fusion Additive Manufacturing System,” In Proceedings
Garcia-Avila, MatiasFoltz, John
ABSTRACT High performance fiber reinforced ceramic rotors have the potential to greatly improve metrics in heavy vehicles such as braking distance, acceleration time, maximum speed, fuel consumption, improved handling, and increased vehicle maximum loads. Three types of carbon ceramic composite brake rotor materials were created using polymer infiltration pyrolysis (PIP) for carbon fiber reinforced silicon oxicarbide, reactive melt infiltration (RMI) for carbon fiber reinforced silicon carbide, and electric field assisted sintering (EFAS) for carbon fiber reinforced silicon carbide-zirconium diboride to investigate the manufacturing of 396mm diameter heavy vehicle brake rotors. The microstructure of parts created by each manufacturing method were discussed and contrasted. The EFAS manufactured rotor created the highest quality part due to extremely fast processing times, uniform material microstructure, and fusing of adjacent fibers in the carbon fiber network. Thermal conductivity was
Rufner, JorgenLeonard, CliffordNutt, StevenNguyen, Kevin
ABSTRACT Fiber reinforced thermoset composites are well known for delivering 50% or more weight savings when compared with steel components while also providing strength, stiffness, and toughness. Nanoparticle additives have been shown to significantly increase the mechanical properties of thermoplastic and thermoset polymer matrices over the base matrix values. Extensive testing and characterization of composites containing graphene nanoplatelets (GnP) has been conducted and reported by XG Sciences’ (XGS) collaborators at the Michigan State University (MSU) Composite Materials and Structures Center. In a recent program with U.S. Army Tank Automotive Research, Development and Engineering Center (TARDEC), MSU investigated lightweight composites for blast and impact protection. High strain rate test facilities as well as high speed photography and non-destructive interferometry-based evaluation techniques were used to evaluate blast performance. The experimental results are presented
Privette, R.Fukushima, H.Drzal, L.T.Robinson, M.
This paper explores the groundbreaking applications of plasma propulsion engines and advanced nanomaterials in low-altitude aircraft, addressing the challenges and recent technological advancements that make such applications feasible. Traditional space plasma thrusters operate effectively in near-vacuum conditions by taking advantage of the ease of plasma ignition at low pressures. However, these thrusters face significant difficulties when operated at near-atmospheric pressures found in low-altitude environments, where plasma ignition is challenging. This paper highlights recent breakthroughs in high-pressure plasma glow discharge technology and the integration of nanomaterials, which together enable the use of plasma propulsion engines in low-altitude aircraft. These innovations offer substantial advantages over conventional engines, including higher efficiency, reduced emissions, and the potential to fundamentally change the propulsion systems of low-altitude aircraft
Ma, XinDing, ShuitingPan, YilunLiu, JinshuoQiao, HuizheYang, Jincai
Human body models have been used for decades to inform efforts in promoting automobile occupant and pedestrian safety. However, many of these models fail to capture the intricacies of individual variability. Cadaveric subjects typically exceed representative age ranges and hence mechanics. Animal subjects typically require specific setups that stray from that which is representative of human crash scenarios. Computational models can only consider so many practical real-world variables. Artificial surrogates, dummies being popular among them, are very popular for reusability and robust data collection. However, even the biomechanically accurate skeletal surrogates available commercially are limited in that they do not consider human variability and skeletal microstructure local variability. The objective of the work herein is to assess computational methods of metastructural variability mimicry by fabrication material. We implement mimicry approaches focusing on bulk isotropic
Hezrony, Benjamin S.C. F. Lopes, PedroBrown, Philip J.
A flexible and stretchable cell has been developed for wearable electronic devices that require a reliable and efficient energy source that can easily be integrated into the human body. Conductive material consisting of carbon nanotubes, crosslinked polymers, and enzymes joined by stretchable connectors, are directly printed onto the material through screenprinting
Researchers have shown that twisted carbon nanotubes can store three times more energy per unit mass than advanced lithium-ion batteries. The finding may advance carbon nanotubes as a promising solution for storing energy in devices that need to be lightweight, compact, and safe, such as medical implants and sensors
Researchers have discovered that minuscule, self-propelled particles called “nanoswimmers” can escape from mazes as much as 20 times faster than other passive particles. The tiny synthetic nanorobots are incredibly effective at escaping cavities within maze-like environments
Butterflies can see more of the world than humans, including more colors and the field oscillation direction, or polarization, of light. This special ability enables them to navigate with precision, forage for food, and communicate with one another. Other species, like the mantis shrimp, can sense an even wider spectrum of light, as well as the circular polarization, or spinning states, of light waves. They use this capability to signal a “love code,” which helps them find and be discovered by mates
When wounds happen, we want them to heal quickly and without complications, but sometimes infections and other complications prevent it. Chronic wounds are a significant health concern affecting tens of millions of Americans
Vehicle light-weighting constitutes a critical component in the automotive sector’s drive to improve fuel economy and reduce greenhouse gas emissions. Among the various options for lightweight materials, thermoplastic foams are distinguished by their durability, low weight, and environmental sustainability. This study explores the manufacturing of novel graphene-filled polypropylene (PP) foam, employing supercritical nitrogen as an eco-friendly substitute instead of conventional chemical foaming agents, and investigated the role of over-molding a solid skin over a foamed core on the flexural strength of the molded component. Our approach is broken down into four distinct investigations—Study I investigated the effect of different graphene content by weight percentage (wt.%), namely 0.1%, 0.5%, and 1%, on flexural properties and foam morphology obtained for 15 wt.% reduction of the PP thermoplastic, thereby helping identify an optimum graphene loading wt.%. Study II broadened the wt
Pradeep, Sai AdityaDeshpande, Amit MakarandShah, BhavikKhan, SaidaFarahani, SaeedSternberg, JamesLi, GangPilla, Srikanth
In this investigation, AA6351 alloy matrix composites with a larger volume proportion of SiC (20 wt%) were fabricated and tested for microstructure and mechanical behavior. Composites were hot extruded from mechanically milled matrix and reinforcements. Hot extrusion uniformly distributed reinforcements in the matrix and strengthened phase interaction. Mechanical ball milling causes AA6351 powder to become more homogeneous, reducing the mean particle size from 38.66 ± 2.31 μm to 23.57 ± 2.31 μm due to particle deformation. The micrograph shows that the SiC particles are equally dispersed in the AA6351 matrix, avoiding densification and reinforcing phase integration issues during hot extrusion. In hot extrusion, SiC particles are evenly distributed in the matrix, free of pores, and have strong metallurgical bonds, resulting in a homogenous composite microstructure. SiC powders and mechanical milling increase microhardness and compressive strength, giving MMC-A 54.9% greater than AA6351
Saiyathibrahim, A.Murali Krishnan, R.Jatti, Vinaykumar S.Jatti, Ashwini V.Jatti, Savita V.Praveenkumar, V.Balaji, K.
Engineers at the University of California San Diego have developed an ultra-sensitive sensor made with graphene that can detect extraordinarily low concentrations of lead ions in water. The device achieves a record limit of detection of lead down to the femtomolar range, which is one million times more sensitive than previous sensing technologies
Borophene is more conductive, thinner, lighter, stronger, and more flexible than graphene, the 2D version of carbon. Now, researchers have made the material potentially more useful by imparting chirality — or handedness — on it, which could make for advanced sensors and implantable medical devices. The chirality, induced via a method never before used on borophene, enables the material to interact in unique ways with different biological units such as cells and protein precursors
Researchers from Tohoku University and Kyoto University have successfully developed a DNA-based molecular controller that autonomously directs the assembly and disassembly of molecular robots. This pioneering technology marks a significant step toward advanced autonomous molecular systems with potential applications in medicine and nanotechnology
Manufacturing flaws and microstructure irregularities pose challenges for the widespread adoption of metal additive manufacturing (MAM) in the US Army. These issues stem from the influence of melt-pool dynamics on the properties of 3D-printed metal parts, which are highly dependent on multiple process parameters. This paper investigates the potential of using electromagnetic fields (EM) to control the melt-pool dynamics in MAM, aiming to eliminate flaws and irregularities. A novel technique is proposed, involving a coil and strategically positioned permanent magnets to actively churn the melt pool. Initial validation of this approach was conducted using COMSOL Multiphysics® through simulation modeling, with ongoing efforts for experimental verification. The findings indicate promising opportunities for enhancing the consistency of 3D printed parts
Karpenko, OleksiiUdpa, SatishUdpa, LalitaHaq, Mahmood
After announcing a ferroelectric semiconductor at the nanoscale thinness required for modern computing components, a University of Michigan team has demonstrated a reconfigurable transistor using that material. The study is featured in Applied Physics Letters
Advances in optical sensors and imaging technologies are ever more rapidly assimilated into how humans interact, understand themselves, and explore the world around them. The scope of inquiry for optical devices is broad and they enable technologies within, such as implanted transdermal bioMEMS devices, and beyond, or as space-flight surveyors deployed as near and deep space instruments. Central to the functionality of modern optical devices, ultra-narrow bandpass (UNBP) thin-film optical filters enable discrimination of sub-nanometer bands inside broad spectra. These filters, pioneered as NIR DWDM filters for the telecommunications industry, are now essential in extracting meaningful signal from imaging and sensing devices operating anywhere between the deep ultraviolet and the mid infra-red bands
University of Rochester Medical Center Rochester, NY
The present work deals with the effects of nano-additives on ternary blend biodiesel fuel added in diesel engine. The ternary blend comprises of mustard oil biodiesel and rice bran oil biodiesel, synthesized by means of transesterification and diesel. Nano-additives used in the current study include carbon nanotubes (CNT) and MgO/MgAl2O4 spinel, which were added in a suitable concentration to the biodiesel. CNTs were procured from the market and MgO/MgAl2O4 spinel was prepared by co-precipitation via ball milling process. The nano-additives were characterized by means of FTIR (Fourier transform infrared spectroscopy), AFM (atomic force microscopy), and DSC (differential scanning calorimetry) analysis. Biodiesel blend samples were prepared such as B20 (20% biodiesel + 80% diesel), B20 + CNT (1000 PPM), B20+MgO/MgAl2O4 spinel (1000 PPM), and B20+CNT+MgO/MgAl2O4 spinel (1000 PPM) were tested against diesel fuel. The maximum increase in brake thermal efficiency (BTE), oxides of nitrogen
Jeyakumar, NagarajanDhinesh, BalasubramanianPapla Venugopal, Inbanaathan
This study examined the effects of lubricant viscosity and metallic content on the oxidation reactivity of diesel particles. In the first part, the factors affecting thermogravimetric analysis (TGA) experiments was discussed and confirmed. The influences of initial soot mass, heating rate, and airflow rate on soot oxidation rate and experimental reproducibility were investigated to develop an optimized TGA method. On the basis of these experiments, an initial soot mass of 2.0 mg, airflow rate of 4.8 L/h, and heating rate of 2.5°C/h were used for all subsequent TGA tests. It could be found that the TGA experiments had high repeatability, and the differences were less than 0.1%. In the second part, a four-cylinder diesel engine was lubricated with seven kinds of lubricant with different viscosity and metallic content by the use of viscosity index improver (VII), antioxidant and corrosion inhibitor (ACI), and ashless dispersant (AD). Particle samples were subjected to TGA to test their
Meng, HaoYang, HeZhang, WeiliXing, JianqiangXu, YanWang, Yajun
This research explores the experimental analysis of titanium alloy using an innovative approach involving a 2–7% carbon nanotube (CNT)-infused cubic boron nitride (CBN) grinding wheel. Employing a full-factorial design, the study systematically investigates the interactions among varied wheel speed, workpiece feed rate, and depth of cut, revealing compelling insights. The integration of CNTs in the CBN grinding wheel enhances the machining performance of titanium alloy, known for its high strength and challenging machinability. The experiment varies CNT infusion levels to assess their impact on material removal rate (MRR) and surface finish. Significantly, MRR is influenced by CNT content, with 5% and above demonstrating optimal performance. The 7% CNT-CBN wheel exhibits a remarkable 61% improvement in MRR over the conventional CBN wheel. Interaction studies highlight the pivotal role of depth of cut, indicating that slower speeds and feeds, combined with increased depth of cut
Stephen, Deborah SerenadeSethuramalingam, Prabhu
The demand for enhanced safety and extended lifespan of brake systems prompts the investigation to increase the static mechanical properties and fatigue resistance of commercial vehicle brake spiders through the incorporation of niobium nanoparticles into a cast iron alloy. This study aims to improve the material structure as well as the static and dynamic mechanical properties of the component. Chemical, microscopic, and mechanical analyses were conducted in samples of the nanostructured alloy and in the spider. A durability test was performed using a structural bench called “Chuker” to assess the potential increase in fatigue life. The Chuker is capable of simulating a real-world brake system condition, including torque magnitudes up to 17.5 kNm, which are the highest to be withstand by the designed brake power. This torque replicates the brake system activation during a vehicle emergency braking. The spiders manufactured with the nanostructured alloy exhibited most uniform
Titton, Angelo PradellaTuzzin, MatheusLopes, Carlos H. R.Marcon, LucasBoaretto, JoelKlein, Aloísio N.Cruz, Robinson C. D.
This research explores the tribological characteristics of brake friction materials, focusing on synthetic iron-based sulfides with unique microstructures. Tribological testing, conducted per the SAE J2522 and SAE J2707 standards across diverse temperatures, reveals the superior performance of brake pads incorporating composite iron sulfide, especially at high temperatures. These pads exhibit stable friction levels and reduced wear compared to those utilizing pure iron sulfide, signifying a noteworthy advancement in overall tribological properties. A comprehensive cross-sectional analysis of friction materials using Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM/EDS) reveals chemical alterations. Pure iron sulfide undergoes extensive oxidation compared to composite iron sulfide, which exhibits oxidation near the friction surface due to differences in the oxidation mechanism because of the differential microstructure. Furthermore, Thermogravimetric Analysis
Jara, Diego ChavezLorenzana, CarlosCotilli, EdoardoSliepcevich, AndreaConforti, Michael
Graphene has been called “the wonder material of the 21st century.” But graphene has a dirty little secret: it’s dirty. Now, engineers at Columbia University and colleagues at the University of Montreal and the National Institute of Standards and Technology are poised to clean things up with an oxygen-free chemical vapor deposition (OF-CVD) method that can create high-quality graphene samples at scale. Their work, published in Nature, directly demonstrates how trace oxygen affects the growth rate of graphene and identifies the link between oxygen and graphene quality for the first time
Membranes of vertically aligned carbon nanotubes (VaCNT) can be used to clean or desalinate water at high flow rate and low pressure. Recently, researchers of Karlsruhe Institute of Technology (KIT) and partners carried out steroid hormone adsorption experiments to study the interplay of forces in the small pores. They found that VaCNT of specific pore geometry and pore surface structure are suited for use as highly selective membranes. The research was published in Nature Communications
Innovators at NASA’s Glenn Research Center have made several breakthroughs in treating hexagonal boron nitride (hBN) nanomaterials, improving their properties to supplant carbon nanotubes in many applications. These inventors have greatly enhanced the processes of intercalation and exfoliation. Both processes are crucial in creating usable nanomaterials and tailoring them for specific engineered applications
Since the beginning of time, people have desired the best materials for production. Metals are often too heavy to be used in manufacturing. Polymer matrix composites (PMC) can be considered more dependable than metals in practical applications because of their high strength-to-weight ratio so it is a good alternative of metals. The article’s objective is to investigate the various PMC properties that are reinforced with carbon fiber. CFRP (Carbon fiber-reinforced polymer) was first made using the hand layup method with carbon fiber as a reinforcement and epoxy resin as a matrix after a thorough literature review. As CFRP have higher stiffness and superior “strength-to-weight ratio,” fiber-reinforced polymer (FRP) composites perform notably better than various conventional metallic materials. The qualities of the matrix can be changed to enhance the characterization of FRP composites. The mechanical qualities of FRP composites have risen as a result of significant advancements in the
Haider, RehanSingh, Pradeep KumarSharma, Kamal
The present work highlights the significance of nanocomposite coatings for their ease of processing and applicability in combating corrosion. Ongoing research is dedicated to the development of an effective nanocomposite hydrophobic coating. A hydrophobic nanocomposite coating was deposited on galvanized iron (GI) using a sol-gel route with polymethylsiloxane (PDMS) reinforced with nano-SiO2. Surface morphology and chemical composition analysis, conducted with scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDAX) and Fourier transform infrared spectroscopy (FTIR), revealed the coating’s structural and compositional attributes. The resulting hydrophobic coating exhibits a water contact angle (WCA) of 104.1°, indicating a 30.45% increase compared to bare GI. Subsequent to these characterizations, the adhesion of the coated GI, rated as 4B per ASTM D3359, is followed by commendable resistance to corrosion, as evidenced by electrochemical tests. The corrosion rate
Kumar, PrakashRamesh, M.R.Doddamani, Mrityunjay
Items per page:
1 – 50 of 1652